Dementia is a complex condition that significantly impacts both patients and their families, and finding effective treatments remains a challenge. However, a recent study highlights that not all cognitive impairments labeled as dementia are irreversible. In fact, certain cases of cognitive decline may be due to reversible causes, such as hepatic encephalopathy (HE), a condition stemming from liver dysfunction, which may be misdiagnosed as dementia. The study, A Possible Reversible Cause of Cognitive Impairment: Undiagnosed Cirrhosis and Potential Hepatic Encephalopathy in Patients with Dementia, sheds new light on the link between liver disease and cognitive decline and suggests that a simple screening tool may help identify these treatable cases.
Understanding Hepatic Encephalopathy
Hepatic encephalopathy occurs when the liver, due to cirrhosis or other forms of chronic liver disease, is unable to filter toxins from the blood. These toxins accumulate and affect brain function, leading to a range of symptoms, including confusion, memory problems, and even severe cognitive impairment that can mimic dementia. If identified, HE can often be reversed with proper treatment once liver function improves.
The overlap in symptoms between HE and dementia can make it difficult for clinicians to differentiate between the two, especially if cirrhosis or liver disease has not been previously diagnosed. This study explored whether undiagnosed cirrhosis and HE may be contributing to dementia diagnoses and whether a non-invasive screening tool—the Fibrosis-4 (FIB-4) index—could help detect these cases.
The Study: Cirrhosis and Cognitive Decline
The study involved a large cohort of over 68,000 patients diagnosed with dementia between 2009 and 2019. Importantly, these patients did not have a prior diagnosis of cirrhosis. Researchers used the FIB-4 index, a calculation based on laboratory values, to screen for undiagnosed cirrhosis. The results were striking: up to 13% of patients with dementia had FIB-4 scores suggesting advanced fibrosis or cirrhosis, indicating that a significant number of these patients may have undiagnosed liver disease.
The study also found that certain risk factors, such as alcohol use disorder, viral hepatitis, and chronic kidney disease, were more prevalent in patients with high FIB-4 scores. These conditions are known to contribute to liver damage and may increase the likelihood of developing HE. Notably, this study confirmed similar findings from previous research conducted in veteran populations, further strengthening the case for liver disease as a contributor to cognitive decline in a broader demographic.
Implications for Diagnosis and Treatment
The identification of cirrhosis and HE as reversible causes of dementia is significant for both patients and clinicians. By using the FIB-4 index as a screening tool, healthcare providers may be able to identify patients with undiagnosed liver disease, who could then receive treatments that improve liver function and reduce cognitive impairment.
This approach is particularly important because treatments for HE, such as lactulose or rifaximin, are widely available and have been shown to be effective in improving cognitive symptoms. Furthermore, lifestyle interventions such as reducing alcohol intake and managing viral hepatitis can help prevent further liver damage and potentially reverse some of the cognitive decline associated with HE.
For patients with dementia, receiving a diagnosis of cirrhosis or HE rather than a neurodegenerative disease could dramatically change the course of their treatment. Instead of focusing solely on managing symptoms of dementia, treatment could target the underlying liver disease, offering hope for cognitive improvement.
A Broader Perspective: Reversible Causes of Dementia
This study highlights just one of several reversible or treatable causes of cognitive decline. Other conditions, such as vitamin B12 deficiency, hypothyroidism, and sleep apnea, can also contribute to cognitive impairment and may be misdiagnosed as dementia if not properly investigated. The key takeaway is that clinicians must consider these reversible causes when evaluating patients with cognitive decline, as appropriate treatment could improve not only cognitive function but also overall quality of life.
In the case of hepatic encephalopathy, the FIB-4 index provides a valuable tool for identifying patients at risk for liver-related cognitive decline. By incorporating this screening tool into routine care for patients with dementia, healthcare providers may be able to uncover hidden cases of cirrhosis and HE, ultimately offering more targeted and effective treatments.
Conclusion
The findings from this study underscore the importance of considering reversible causes of dementia in clinical practice. Undiagnosed cirrhosis and hepatic encephalopathy may contribute to cognitive decline in a significant number of patients with dementia, and the FIB-4 index offers a simple, non-invasive way to screen for liver disease in this population. By identifying and treating these reversible causes, we have the potential to improve outcomes for many patients who would otherwise face the devastating prognosis of dementia.
